1. Technical Field of the Invention
The present invention relates to electric wire connecting structure of a lamp unit, and particularly to electric wire connecting structure between an electric wire and a lamp unit when the lamp unit such as a room lamp or the like is attached to a lamp attaching window of an interior wall material such as a roof trim or the like that covers a vehicle body panel.
2. Related Art
In case that a lamp unit such as a room lamp or a courtesy lamp is attached to an interior wall material such as a roof trim that covers a vehicle body panel or a door trim, each lamp unit has been attached to a lamp-attaching window opened in the interior wall material.
FIG. 6 is a sectional view for explaining a related example of the lamp unit attaching structure, which has been disclosed in JP-A-4-57454U and JP-A-5-131882. As shown in FIG. 6, a room lamp 13 is attached to a lamp attaching window 15 opened in a roof trim 3 used as an interior wall material for covering a body ceiling 2 that is a body panel of a vehicle body 1.
The room lamp 13 is mainly composed of a housing 6, a bulb (electric bulb) 9 and a cover lens 5. The bulb 9 is inserted between bus bars 8 functioning as a bulb contact fixed to the housing 6, and one of the bus bars 8 is connected through a coated electric wire 21 to a room lamp side-connector 11. Tapping screws 7 for fixing the room lamp 13 to a roof trim 3 are attached to the housing 6. Attaching holes 4, to which the tapping screws 7 are inserted, are provided at the roof trim 3.
In case that the above room lamp 13 is attached to the roof trim 3, a body side connector 12 of a roof harness 10 is pulled down once from a lamp-attaching window 15 of said roof trim 3, and fitted and connected to the room lamp side connector 11 of the room lamp 13. Thereafter, the connectors 11, 12 are respectively located on the roof trim 3 together with the roof harness 10 through the lamp-attaching window 15, and then the room lamp 13 is fixed to the lamp-attaching window 15 by the tapping screws 7.
In case that one of the bus bars 8 is connected as an electric wire connecting terminal to a coated electric wire 21 of the room lamp-side connector 11 as described above, as shown in FIG. 7, the coated electric wire 21 is press-fitted and connected to a press-fitting terminal portion 22 provided at the bus bar 8 functioning as the electric wire connecting terminal.
The press-fitting terminal portion 22 includes a pair of press-fitting pieces 23, 23 that are provided erectly for a bottom plate 8a in parallel, and a U-shaped press-fitting groove 24 that is cut from an upper end edge to the downside is formed in each of these press-fitting pieces 23.
When the coated electric wire 21 including a round conductor 21b having a round section is forced into the press-fitting groove 24, the press-fitting groove 24 is cut into an insulating coat 21a and the round conductor 21b is press-fitted and connected to the press-fitting groove 24, so that the coated electric wire 21 of the room lamp side-connector 11 and the bus bar 8 of the room lamp 13 are electrically connected to each other.
However, the electric wire for connecting the roof harness 10 on the vehicle body side to the room lamp 13 is not limited to the coated electric wire 21 shown in FIG. 7. Recently, a flat circuit body such as FFCs (flexible flat cable) 40 and 100 as shown in FIG. 8 is used as such the electric wire.
And, in case of an electric wire formed by covering the plural round conductors 40b with an insulating coat 40a such as the FFC 40 shown in FIG. 8A, the round conductor 40b is press-fitted and connected to the press-fitting groove 24 of the press-fitting terminal portion 22 as shown in FIG. 7, whereby the bus bar 8 of the room lamp 13 and the roof harness on the vehicle body side can be electrically connected to each other. However, in case of an electric wire formed by covering flat conductors 100b having rectangular sections with an insulating coat 100a such as the FFC 100 shown in FIG. 8B, it cannot be press-fitted and connected to the press-fitting terminal portion 22 as shown in FIG. 7.
In order to connect the above FFC 100 having the flat conductors 100b to the room lamp 13, it is necessary to use an electric wire-connecting terminal having each connecting terminal portion for welding or for piercing. Therefore, the room lamp 13 requires rearrangement of the electric wire connecting terminals that are different in the connecting terminal portion according to the shape of the wire conductor on the body side, and it must hold the plural kinds of electric wire connecting terminals, so that there is a problem that wide application is low.
Accordingly, an object of the invention is to solve the above problem and to provide electric wire connecting structure of a lamp unit in which connection to an electric wire on a vehicle body side can be easily performed regardless of mode of a wire conductor and wide application is high.
The above object of the invention is achieved by electric wire connecting structure comprising:
a lamp unit attachable to a lamp-attaching window provided in an interior wall material covering a vehicle body panel, the lamp unit including a design portion and a lamp functional portion, and
an electric wire connecting terminal provided on the lamp functional portion, wherein the electric wire connecting terminal includes a round conductor connecting portion and a flat conductor connecting portion which correspond to a conductor shape of an electric wire lain on a body panel side of the interior wall material and fixed to the electric wire connecting terminal.
According to the above constitution, in case that a conductor of an electric wire that is laid on the body panel side and fixed to the electric wire connecting terminal is a round conductor, the electric wire can be fixed to the round conductor connecting portion. On the other hand, in case that a conductor of an electric wire is a flat conductor, the electric wire can be fixed to the flat conductor-connecting portion.
Namely, regardless of mode of the fixed wire conductor, the electric wire on the vehicle body side can be reliably fixed to the electric wire connecting terminal, and it is not necessary to prepare the plural kinds of electric wire connecting terminals according to the shape of the wire conductor.
Accordingly, productivity of the lamp unit improves and wide application thereof heightens, so that a manufacturing cost can be reduced.
Preferably, the electric wire connecting terminals are put side by side on a lamp-attaching portion of the lamp functional portion, and the round conductor connecting portion including a press-fitting terminal portion is arranged on a more distant side from the lamp-attaching portion than the flat conductor connecting portion.
In this case, the round conductor-connecting portion becomes a press-fitting terminal portion that is easy in connection working. Therefore, connecting work performance of the electric wire in relation to the lamp functional portion improves.
Further, since the press-fitting terminal portion is arranged on the distant side from the lamp-attaching portion that becomes a heat generator, its terminal portion is difficult to receive influence of heat and easy to obtain connection reliability.